Abstract:

• Capturing a freely suspended pendulum ram
• Returning the pendulum to the freely-programmable trigger angle
• Connection with a safety switching device via Ethernet TCP/IP with Modbus TCP protocol

Criteria in Favor of Jetter AG:

The general manager of the company in particular appreciates the direct response of the servo amplifier parameters. All parameters can be accessed in real time and are executed directly. It is therefore possible for him to react flexibly to a wide range of axis applications. Integration of the entire periphery including the servo-axes with the JetSym ST higher-level language instead of conventional PLC languages enables fast machine start-up. He therefore discovered that only 25 percent of the commissioning time including follower was required for servo-axes. Initial coupling via Ethernet with MODBUS-TCP did not require any noteworthy length of time. Mr. Frentzel, an ambitious higher-level language programmer, appreciates the option of programming JetControl via the intranet or wireless LAN.

Technical Description of the Production Plant:

A great deal is in flux in the field of material testing. This is particularly true in the plastics sector, but there are also a large number of new blends, alloys and processes in other fields of material testing which require series tests for determining the notch impact strength. These tests used to involve a great deal of manual labor, but an automatic pendulum lift together with handing units now permits automation and therefore testing of hundreds of samples without human intervention.

One element of this system is to "capture" the pendulum after release and movement and to return it to the freely programmable starting position. This is performed by a control system which registers the rising angle (a fast cycle time is important) and a servo-drive which runs synchronously to the pendulum motion without affecting the pendulum itself. There are two principles for capturing the pendulum:

• For large and heavy pendulums
  At the maximum rising angle a positive locking coupling is activated which "grips" the pendulum when it swings back, engaging the servo-drive which takes the pendulum back to the home position.

• For small and light pendulums
  The maximum rising angle is determined. An arm running synchronously with the pendulum returns the pendulum to the home position with the servo-drive when it swings back.

The resulting data is collected and written into a database using Ethernet TCP/IP. The parameters release angle, rising angle or the angle difference can be used to determine the impact energy or the notch impact strength.

Components used:

Control Systems:

• JetControl 241
• JX2-ID8
• JX2-OD8
• JX2-CNT1

Intelligent terminals:

• JX-SIO

Servo motors and servo amplifiers:

• Servo motors of the JL, JK and JH series
• Servo amplifier JetMove 206

Other components:

• Festo valve terminal CPX on the Jetter system bus
• Communication via Ethernet MODBUS-TCP with Pilz safety devices